404 On the Neroous Systenis of 
qworld which was a twin of rather small size; and 
it is worthy of remark, that a considerable pro- 
portion of these defective fetuses has beer 
twins.t As far as F could determine from an 
exterior view it was not entirely destitute of 
brain, nor did it present any other deformity or 
defect ; but I had not an opportunity of ex= 
amining it by dissection. Many of these mon- 
sters, however, have “exhibited other kinds of 
deformity.’ A tumor, containing a thin watery 
fluid, has im several instances been found attached 
to the base of the skull at its fore, or back part— 
A hare-lip, sometimes with, at other times without 
a division of the upper jaw and palate, has been 
observed—The affection of the spine and spinal 
matrow, termed spina bifida or hydrorachitis, 
has been occasionally met with—An umbilical 
hernia of very large size has also been found— 
Examples of all these complicated deformities’ 
may be seen described and admirably delineated 
in Sandifort’s Museum Anatomicum Tab, 122, 
223, 124, 126. 
_ A fetus was lately born in Manchester, in’ 
which the brain was not only defective, but 
_ +t The very curious acephalous monster, described by 
Curtius, was a twin. See Sandifort’s Thesaur. Dissert. 
&c. Tom.2. The monsters, described by Drs, Monro 
~and Clarke, to be mentioned more particularly hereafter, 
were also twins, 
